CompTIA CompTIA Certifications N10-008 Questions & Answers

• Question 351:

  A network architect needs to create a wireless field network to provide reliable service to public safety vehicles. Which of the following types of networks is the best solution?

  A. Mesh

  B. Ad hoc

  C. Point-to-point

  D. Infrastructure

  Correct Answer: A

  A mesh network is the best solution for creating a wireless field network to provide reliable service to public safety vehicles. A mesh network is a type of wireless network that consists of multiple nodes that communicate with each other directly or through intermediate nodes, forming a web-like topology. A mesh network does not rely on a central access point or router, but rather on the cooperation and coordination of the nodes themselves. A mesh network has several advantages for public safety applications, such as12: High availability and resilience: A mesh network can automatically route around failures or congestion, ensuring that the network remains operational even if some nodes are damaged or disconnected. A mesh network can also self-heal and self- configure, adapting to changes in the network topology or environment. Extended coverage and scalability: A mesh network can extend the wireless signal beyond the range of a single node, by using other nodes as relays or repeaters. A mesh network can also accommodate more nodes and devices, by adding more links and paths between them. Low cost and easy deployment: A mesh network can reduce the cost and complexity of installing and maintaining a wireless infrastructure, by eliminating the need for expensive cabling, towers, or antennas. A mesh network can also be deployed quickly and flexibly, by simply adding or removing nodes as needed. A mesh network is especially suitable for public safety vehicles, because it can provide reliable wireless communication in challenging scenarios, such as12: Disaster response: A mesh network can be deployed rapidly in areas where the existing wireless infrastructure is damaged or unavailable, such as after an earthquake, flood, or fire. A mesh network can also support emergency services, such as fire fighting, search and rescue, or medical assistance, by enabling data, voice, and video transmission among the responders and command centers. Mobile surveillance: A mesh network can enable real-time monitoring and control of public safety vehicles, such as police cars, ambulances, or drones, by providing high-bandwidth and low-latency wireless connectivity. A mesh network can also support video streaming, location tracking, remote sensing, or analytics applications for public safety purposes. Event management: A mesh network can enhance the security and efficiency of large-scale events, such as concerts, festivals, or parades, by providing wireless coverage and capacity for the event organizers and participants. A mesh network can also support crowd management, traffic control, or public announcement applications for event management. The other options are not the best solutions for creating a wireless field network to provide reliable service to public safety vehicles. An ad hoc network is a type of wireless network that consists of devices that communicate with each other directly without any central coordination or infrastructure. An ad hoc network is simple and flexible, but it has limited scalability and performance3. A point-to-point network is a type of wireless network that consists of two devices that communicate with each other over a single link. A point-to- point network is fast and secure, but it has limited coverage and functionality. An infrastructure network is a type of wireless network that consists of devices that communicate with each other through an access point or router. An infrastructure network is stable and robust, but it has high cost and complexity.

• Question 352:

  A network administrator needs to create an SVI on a Layer 3-capable device to separate voice and data traffic. Which of the following best explains this use case?

  A. A physical interface used for trunking logical ports

  B. A physical interface used for management access

  C. A logical interface used for the routing of VLANs

  D. A logical interface used when the number of physical ports is insufficient

  Correct Answer: C

  An SVI, or switched virtual interface, is a logical interface that is created on a Layer 3- capable device, such as a multilayer switch or a router. An SVI is associated with a VLAN and can be used to route traffic between different VLANs on the same device or across multiple devices. An SVI can also provide management access, security features, and quality of service (QoS) for the VLAN. An SVI is different from a physical interface, which is a port that connects to a physical device or network. A physical interface can be used for trunking, which is a method of carrying multiple VLANs over a single link, or for connecting to a single VLAN. An SVI is also different from a subinterface, which is a logical division of a physical interface that can be assigned to different VLANs.

• Question 353:

  An organization recently connected a new computer to the LAN. The user is unable to ping the default gateway. Which of the following is the most likely cause?

  A. The DHCP server is not available.

  B. An RFC1918 address is being used

  C. The VLAN is incorrect.

  D. A static IP is assigned.

  Correct Answer: A

  The DHCP server is not available is the most likely cause of the issue where a new computer is unable to ping the default gateway. DHCP stands for Dynamic Host Configuration Protocol, which is a network protocol that automatically assigns IP addresses and other configuration parameters to clients on a network. The default gateway is the IP address of the router or device that connects a local network to other networks, such as the internet. Pinging is a network utility that tests the connectivity and reachability between two devices by sending and receiving echo packets. If the DHCP server is not available, the new computer will not be able to obtain an IP address or other configuration parameters, such as the default gateway, from the DHCP server. This will prevent the new computer from communicating with other devices on the network or the internet, resulting in ping failure.

• Question 354:

  Which of the following devices and encapsulations are found at me data link layer? (Select TWO)

  A. Session

  B. Frame

  C. Firewall

  D. Switch

  E. Packet

  F. Router

  Correct Answer: BD

  The data link layer is responsible for defining the format of data on the network and providing physical transmission of data. Devices that operate at this layer include switches and network interface cards (NICs). Encapsulations that are used at this layer include frames, which are units of data that contain a header, payload, and trailer. Frames are used to identify the source and destination of data on the network and to perform error detection.

• Question 355:

  Which of the following IP packet header fields is the mechanism for ending loops at Layer 3?

  A. Checksum

  B. Type

  C. Time-to-live

  D. Protocol

  Correct Answer: C

  The time-to-live (TTL) field is the mechanism for ending loops at Layer 3, which is the network layer of the OSI model. The TTL field is an 8-bit field that indicates the maximum time or number of hops that an IP packet can travel before it is discarded. Every time an IP packet passes through a router, the router decrements the TTL value by one. If the TTL value reaches zero, the router drops the packet and sends an ICMP message back to the source, informing that the packet has expired. This way, the TTL field prevents an IP packet from looping endlessly in a network with routing errors or cycles123. The other options are not mechanisms for ending loops at Layer 3. The checksum field is a 16-bit field that is used to verify the integrity of the IP header. The checksum field is calculated by adding all the 16-bit words in the header and taking the one's complement of the result. If the checksum field does not match the calculated value, the IP packet is considered corrupted and discarded12. The type field, also known as the type of service (TOS) or differentiated services code point (DSCP) field, is an 8-bit field that is used to specify the quality of service (QoS) or priority of the IP packet. The type field can indicate how the packet should be handled in terms of delay, throughput, reliability, or cost12. The protocol field is an 8-bit field that is used to identify the transport layer protocol that is encapsulated in the IP packet. The protocol field can indicate whether the payload is a TCP segment, a UDP datagram, an ICMP message, or another protocol12.

• Question 356:

  A company upgrades its network and PCs to gigabit speeds. After the upgrade, users are not getting the expected performance.

  Technicians discover that the speeds of the endpoint NICs are inconsistent. Which of the following should be checked first to troubleshoot the issue?

  A. Speed mismatches

  B. Load balancer settings

  C. Devices' duplex settings

  D. Office wiring category

  Correct Answer: C

  Duplex settings determine how data is transmitted and received over a network. If the devices have inconsistent duplex settings, such as half-duplex and full-duplex, they may experience performance issues, collisions, and errors. To troubleshoot the issue, the technicians should check the devices' duplex settings and make sure they match the network's configuration.

• Question 357:

  A junior network administrator is auditing the company network and notices incrementing input errors on a long-range microwave interface. Which of the following is the most likely reason for the errors?

  A. The parabolic signal is misaligned.

  B. The omnidirectional signal is being jammed.

  C. The omnidirectional signal is not strong enough to receive properly.

  D. The parabolic signal uses improper routing protocols.

  Correct Answer: A

  A long-range microwave interface is a type of wireless communication that uses high- frequency radio waves to transmit and receive data over long distances. A long-range microwave interface typically uses a parabolic antenna, also known as a dish antenna, to focus the radio waves into a narrow beam that can travel farther and with less interference than an omnidirectional antenna, which radiates the radio waves in all directions1. One of the most common causes of input errors on a long-range microwave interface is the misalignment of the parabolic antenna. Input errors are errors that occur when the receiver cannot properly decode or process the incoming signal. If the parabolic antenna is not aligned correctly with the transmitter, the receiver may not be able to capture the full strength of the signal, or it may pick up unwanted noise or interference from other sources. This can result in corrupted or lost data, which will increase the input error count23. To troubleshoot this issue, the junior network administrator should check the alignment of the parabolic antenna and make sure it is pointing directly at the transmitter. The administrator can use tools such as a spectrum analyzer, a signal strength meter, or a path alignment tool to measure and adjust the signal quality and alignment of the antenna24. The other options are not likely reasons for the input errors on a long-range microwave interface. A long-range microwave interface does not use an omnidirectional signal, so it cannot be jammed or weakened by other sources. The parabolic signal does not depend on the routing protocols used by the network, so it cannot be affected by improper routing protocols.

• Question 358:

  A user is unable to reach any resources on the internet. A technician goes to the site and obtains the following output from the workstation:

  

  Which of the following commands should the technician use to correct the issue?

  A. route ADD 0.0.0.0 MASK 0.0.0.0 10.10.51.10 metric 35

  B. route CHANGE 10.10.51.0 MASK 255.255.255.255 10.10.52.1 metric 5

  C. route CHANGE 10.10.51.255 MASK 255.0.0.0 On-Link metric 1

  D. route DELETE 127.255.255.255

  Correct Answer: A

  The route command is used to view and manipulate the IP routing table in Windows operating systems456 The routing table contains information about how to reach different network destinations. The output from the workstation shows that the routing table does not have a default gateway, which is a router that forwards packets to other networks that are not directly connected to the local network. A default gateway is usually specified by a route with a destination of 0.0.0.0 and a netmask of 0.0.0.0, which matches any IP address. To correct the issue, the technician can use the route ADD command to add a default gateway to the routing table. The syntax of the command is: route ADD MASK metric The destination and netmask parameters should be 0.0.0.0 to indicate a default route. The gateway parameter should be the IP address of the router that can reach the internet, which is 10.10.51.10 in this case. The metric parameter is an optional value that indicates the cost or preference of the route, which can be used to choose between multiple routes to the same destination. A lower metric means a higher preference. The metric parameter can be any integer between 1 and 9999. In this case, the metric parameter can be 35 or any other value. Therefore, the correct command is: route ADD 0.0.0.0 MASK 0.0.0.0 10.10.51.10 metric 35

• Question 359:

  Which of the following authentication protocols should be used when securing a basic wireless network? (Select two).

  A. WPA2

  B. RDP

  C. WPA

  D. SSL

  E. SNMP

  F. EAP

  Correct Answer: AC

• Question 360:

  A customer is adding fiber connectivity between adjacent buildings. A technician terminates the multimode cable to the fiber patch panel. After the technician connects the fiber patch cable, the indicator light does not come on. Which of the following should a technician try first to troubleshoot this issue?

  A. Reverse the fibers.

  B. Reterminate the fibers.

  C. Verify the fiber size.

  D. Examine the cable runs for visual faults.

  Correct Answer: A

  One of the most common causes of fiber connectivity issues is the reversal of the fibers. This means that the transmit (TX) and receive (RX) ports on one end of the fiber link are not matched with the corresponding ports on the other end. For example, if the TX port on one device is connected to the TX port on another device, and the same for the RX ports, then the devices will not be able to communicate with each other. This can result in no indicator light, no link, or no data transmission12. To troubleshoot this issue, the technician should first try to reverse the fibers. This can be done by swapping the connectors at one end of the fiber patch cable, or by using a crossover adapter or cable that reverses the polarity of the fibers. The technician should then check if the indicator light comes on and if the devices can communicate properly12. The other options are not the first steps to troubleshoot this issue. Reterminating the fibers is a time-consuming and costly process that should be done only if there is evidence of physical damage or poor quality of the termination. Verifying the fiber size is not relevant in this scenario, as multimode fiber is compatible with multimode fiber, and any mismatch in core diameter or bandwidth would result in high attenuation, not complete loss of signal. Examining the cable runs for visual faults is a useful technique, but it requires a special tool called a visual fault locator (VFL) that emits a visible red light through the fiber and shows any breaks or bends along the cable. However, a VFL cannot detect polarity issues or connector problems, so it is not sufficient to troubleshoot this issue